The invention relates to a fuel atomization system and method and more particularly the invention relates to a fuel atomization system and method that utilizes an electrolysis system to produce the desired atomization and improvement of the combustion process.
The ability to utilize coal and other low-grade fuels effectively is becoming increasingly important as the worldwide supply of more conventional fuels is depleted. The technology of coal-water fuels has been under development since the early 1980""s and such development work continues to receive active support from the energy community.
One approach that offers promise for increasing coal utilization consists of mixing pulverized coal with water to produce a slurry. This provides the coal in a liquid form that can be more easily injected and used in boilers or, potentially in power producing equipment such as diesel engines and gas turbines. Commercial acceptance of this approach however has been limited for several reasons. One reason for the limited acceptance is the difficulty of achieving acceptable atomization of the viscous slurry. Another reason for the limited acceptance is the difficulty of igniting the fuel and sustaining stable combustion. This is due to the inherent quenching effect of the water and the low reactivity of the coal. The invention disclosed herein provides the capability of effectively dealing with both of these reasons for limited acceptance.
The simplest conventional method of atomization is comprised of pressurizing the liquid fuel and injecting it at high velocity into the combustion air. The resulting shear created at the free surface between the liquid fuel and the surrounding air provides the force required for disintegration of the liquid fuel into small droplets. This approach has not been practical for coal-water fuels. The high injection velocities required to atomize the viscous fuel and the abrasive nature of the ash contained in the coal combine to cause rapid wear of the injector orifice.
Twin-fluid atomizers offer a more satisfactory approach for coal-water fuels. In this type of design, a second coflowing gaseous fluid, such as air or steam, is introduced into the atomizer and is injected along with the liquid and a high relative velocity is created between the two streams due to their difference in density. This provides the required atomization energy without causing excessive abrasion of the injector surfaces. In addition, the required operating pressure is considerably less with a two-fluid atomizer than with the simple hydraulic atomizer.
The effervescent atomizer is a particularly effective variation of the basic twin-fluid configuration. In this approach, the second fluid is introduced into the atomizer so that it is distributed in the form of small bubbles throughout the liquid stream. When this bubbly stream exits the atomizer it is distributed in the form of small bubbles throughout the liquid stream. When the bubbly stream exits the atomizer, the intimately mixed gas component rapidly expands causing efficient atomization of the liquid.
Although the twin-fluid and effervescent atomizers have solved a number of the problems associated with the atomization of low grade fuels, known methods of atomization do not provide the means to promote the stable, efficient combustion of these fuels required for their widespread commercial acceptance.
The foregoing illustrates limitations known to exist in present devices and methods. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.
In one aspect of the present invention, this is accomplished by providing an atomization system that includes a flow conduit for flowing a fuel/water mixture to a downstream object of interest. The flow conduit defines a flow chamber with an electrolysis system located in the chamber at an upstream conduit end and an atomizer located at a downstream conduit end. The fuel/water mixture is in the liquid phase as it flows through the electrolysis system where gas bubbles are generated and in this way, effective atomization occurs as the mixture is flowed downstream through the atomizer.
The foregoing and other aspects will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawing figures.